Technical Field
The present disclosure relates generally to the field of optical communications, and particular to an optical module.
Related Art
An optical module is a core device in an optical communications system. An optical module performs mutual conversion between an optical signal and an electrical signal.
FIG. 1 is a schematic diagram of an optical module. As shown in FIG. 1, an optical module includes an upper housing C1, a lower housing C2, an optical component CH, and a circuit board 103. The optical component CH is connected to the circuit board using a flexible circuit board. The upper housing and the lower housing form a cavity that encloses the optical component and the circuit board. At one end of the optical component is an optical interface of the optical module. An input optical fiber is connected to the optical interface. At the end of the circuit board is an electrical interface of the optical module. The electrical interface is configured to be connected to an external electronic system.
A processor, an optical chip, and an edge connector are further included on the surface of the circuit board. Some pins of the processor and the optical chip may be separately connected to pins of the edge connector. The edge connector includes multiple pins such as a ground pin, a power pin, and a data pin.
The edge connector of the optical module may be configured to be inserted into an edge connector socket of an external system or system cage. The edge connector socket may include contact spring plates having a one-to-one correspondence to the pins of the edge connector. To integrate the optical module with the external electronic system, the circuit board is inserted into the edge connector socket. When the circuit board is inserted, the contact spring plates nip the edge connector of the circuit board, forming electrical contact with the pins of the edge connector. A power spring plate may become correspondingly in contact with a power pin. Likewise, a data spring plate may become in contact with a data pin, and a ground spring plate may become in contact with a ground pin. The external electronic system supplies power to the processor and the optical chip using the power pin of the edge connector, exchanges data with the processor and the optical chip using the data pin, and provides a ground connection with the processor and the optical chip using the ground pin.
The edge connector of the circuit board may include a row of connector pins. Functions of edge connector pins may be specified in detail according to industry standards governing optical communications and optical modules such that the edge connector pins can meet power requirement and data communication requirement of the processor and the optical chip of the optical module. The industry standards specify correspondence relationship between edge connector pins, the processor, and the optical chip.
The number of pins in a row of an edge connector may be limited by the space available for the edge connector on the circuit board. As numbers of optical chips and processors of the optical module increase, more pins may need to be provided in the edge connector.
FIG. 2 is a schematic diagram of an edge connector. Because of the correspondence relationship between the edge connector pins, the processor, and the optical chip, when an extra optical chip is added to the optical module, an additional row of edge connector pins may be added to the edge connector. Specifically, a first row of edge connector pins may correspond to a first set of optical chips, and a second row of edge connector pins may correspond to another set of optical chips.
Correspondingly, the external electronic system may provide a first row of contact spring plates and a second row of contact spring plates, to provide connection to the double-row edge connector pins.
In a power-on process for the optical module, power is first supplied to the optical module, and then data communication is activated. The first row of contact spring plates and the second row of contact spring plates separately include power spring plates and ground spring plates. The positions of power pins and power spring plates may be configured to be the same for each row of edge connector pins and the socket, in order to avoid electric damage caused by contacting a power spring plate in one row with data pin of another row when the edge connector pins are inserted into a corresponding socket of contact spring plates.
In a double-row configuration and even when power pins are aligned between the first and second rows, when the edge connector pins are inserted into a corresponding socket of contact spring plates, the power pin of the second row of the edge connector pins is first in contact with the power spring plate of the first row spring plates of the socket. Such contact is subsequently lost as the edge connector pins is continually inserted into the socket such that the power pin of the second row is inserted between the power spring plate of the first row and the power spring plate of the second row in the socket. As the edge connector pins is inserted even further, the power pin of the second row is again in contact with external power source when it becomes in contact with the power spring plate of the second row in the socket. This insertion process causes power cycles in the processor and the optical chip whose power is supplied through the power pin on the second row of the edge connector. As a result, the processor and the optical chip may be intermittently powered and may not start normally, and may be susceptible to damage.